Methods and systems for thermal forming an object

ABSTRACT

A method and system for thermal forming an object. A mold is provided, a shape of which corresponds to a desired shape of the object. A material is inserted into a heating area, and the material is heated using a plurality of independently controllable heat sources that heat different areas of the material. The heated material is then disposed over or into at least a portion of the mold so as to deform the material. The deformed material may then be trimmed so as to form the object.

RELATED APPLICATIONS

The present application claims priority from U.S. Provisional Application No. 61/475,212 (Attorney Docket No. 83289-804351), filed on Apr. 13, 2011, which is incorporated by reference into this application in its entirety for all purposes.

BACKGROUND OF THE INVENTION

The present invention relates to methods and systems for thermal forming an object. More specifically, the present invention relates to methods and systems for selectively heating a material to be disposed over or into a mold.

Various techniques for thermal forming objects are currently used in the art. These include thin-gauge thermal forming techniques, where thin sheets or films (usually having a thickness of less than 0.6 inches) of plastic are used to form relatively portable objects such as dishware, food packaging products, plastic blisters for packaging of pharmaceutical products, and the like. These also include thick-gauge thermal forming techniques, where thicker sheets (usually having a thickness greater than 1.2 inches) of plastic are used to form relatively bulky objects, such as cosmetic surfaces on automobiles, medical equipment, kitchen appliances, and the like.

In many techniques, the sheeted plastic material is first heated, and then formed into the shape of the desired object using a mold. Heating is typically done with a single unit including one or more heating coils. Numerous problems arise with uneven distributions of heat in many existing systems. In the case of a single heating coil, portions of the plastic located under the heating coil are heated to a much greater extent than portions of the plastic located away from the heating coil. In the case of multiple heating coils, portions of plastic located under the heating coils are heated to a greater extent than portions of the plastic located between heating coils.

Uneven heat distributions cause various problems in the thermal forming process. For example, the malleability of the heated plastic varies, resulting in inaccurate forming over a mold. For another example, portions of the heated plastic may be heated too much so as to provide a desired average heat and thus malleability to form the plastic over the mold, where the overheating causes deformations, weaknesses, etc. in the plastic composition. In applications which require high precision molds, such as in the formation of dental appliances that must accurately conform to a mold within a tolerance of mere micrometers, these problems create significant burdens and inefficiencies in the thermal forming process, and potentially deficiencies in product effectiveness.

Further, existing techniques do not take into consideration changes or differences in plastic and/or molds. That is, the same heating coils and amount of heat is produced even if the plastic sheets (or molds) provided at the input are changed (to be thicker or thinner) for forming different objects. In this case, suboptimal heating is performed on the subsequent sheets, resulting again in inefficiencies and product expansion limitations.

Accordingly, it is desirable to overcome such deficiencies so as to improve the quality of objects that are formed by thermal forming, increase the efficiency of manufacturing objects via thermal forming, reduce the amount of waste generated by current thermal forming systems and processes, and increase the number of applications for which a single thermal forming system may be used.

BRIEF SUMMARY OF THE INVENTION

The present invention provides methods, systems, and apparatus's for thermal forming an object by selectively heating a material to be disposed over or into a mold.

In one embodiment, a method, system, or apparatus for thermal forming an object is provided. The method can include providing a mold, for example, operatively coupled within a vacuum chamber. A material (e.g., plastic) may then be inserted into a heating area and heated using a plurality of independently controllable heat sources that heat different areas of the material. By independent control of the heat sources heating different areas, heating of the material can be improved or better tailored so as to, e.g., ensure better or more even distribution of heat across the entire material. The heated material may be disposed over or into at least a portion of the mold by, for example, creating a vacuum in the vacuum chamber.

For a fuller understanding of the nature and advantages of embodiments of the present invention, reference should be made to the ensuing detailed description and accompanying drawings. Other aspects, objects and advantages of the invention will be apparent from the drawings and detailed description that follows. However, the scope of the invention will be fully apparent from the recitations of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a system for thermal forming an object according to an embodiment of the present invention.

FIG. 2A is a perspective view of a simplified heating element according to a first embodiment.

FIG. 2B is a side view of the simplified heating element shown in FIG. 2A.

FIG. 3A is a perspective view of a simplified heating element according to a second embodiment.

FIG. 3B is a side view of the simplified heating element shown in FIG. 3A.

FIG. 4A is a perspective view of a simplified heating element according to a third embodiment.

FIG. 4B is a side view of the simplified heating element shown in FIG. 4A.

FIG. 5A shows heated portions of a material according to a first embodiment.

FIG. 5B shows heated portions of a material according to a second embodiment.

FIG. 5C shows heated portions of a material according to a third embodiment.

FIG. 6 shows a heating element according to an embodiment.

FIG. 7 is a flowchart depicting example operations for thermal forming an object in accordance with a first embodiment.

FIG. 8 is a flowchart depicting example operations for thermal forming an object in accordance in accordance with a second embodiment.

FIG. 9 is a diagram of an electronic computing device according to an example embodiment.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention provide methods and systems for thermal forming an object by selectively heating a material to be disposed over or into a mold.

In one embodiment, a method for thermal forming an object is provided. The method can include providing a mold operatively coupled to a vacuum chamber. A material (e.g., plastic, polymer sheet, toys, etc.) may then be inserted into a heating area and heated using a plurality of independently controllable heat sources that heat different areas of the material. By independent control of the .heat sources heating different areas, heating of the material can be improved or better tailored, e.g., so as to ensure better or more even distribution of heat across the entire material. The heated material may be disposed over or into at least a portion of the mold by, for example, creating a vacuum in the vacuum chamber.

In another embodiment, a system for thermal forming an object is provided. The system includes a movable element operable to insert a material into a heating area. For example, the movable element may include rollers that transport the material through the heating area and to and through other elements of the system. The system also includes a heating unit operable to heat the material using a plurality of independently controllable heat sources that heat different areas of the material when the material is located in the heating area. The system may also include a controller electronically coupled to the heat sources for controlling an output of the heat sources. The system may further include an object forming element, operatively coupled to a mold, positioned to receive the heated material, and configured to dispose the heated material over or into at least a portion of the mold. In one embodiment, the object forming element includes a top chamber and a bottom chamber that may engage to form a vacuum chamber.

In yet another embodiment, a heating element is provided for heating a material used to form an object in a thermal forming process. The heating element includes a plurality of independently controllable heat sources operable to heat different portions of the material. The heat sources may include, for example, carbon emitters. The heating element also includes at least one temperature sensor for monitoring a temperature of one or more portions of the material. The temperature sensor may include, for example, an infrared temperature sensor disposed on a side of the material opposite a side which the heat sources are disposed. The heating element may also include a control device electrically coupled to the heat sources and the temperature sensor for controlling the heat sources based on the monitored temperature. By monitoring the temperature and controlling the heat sources based on the monitored temperature, heating of the material can be narrowly tailored so as to ensure an even distribution of heat across select, desired portions of the material.

FIG. 1 shows a system 100 for thermal forming an object according to an embodiment of the present invention. System 100 includes a material 10 to be formed into an object, a movable element 12 for moving material 10, and a supporting member 14 for physically supporting various elements of the system 100. System 100 also includes a heating element 20 for selectively heating material 10. Heating element 20 includes a heating unit 22 for heating material 10, and a temperature sensor 24 for monitoring a temperature of material 10. System 100 further includes an object forming element 30 for disposing the heated material 10 over or into at least a portion of a mold 32. Object forming element 30 includes a top chamber 34, a bottom chamber 36 and a mold carrier 38, and causes deformed portions 39 to be formed in material 10. System 100 also includes an extracting element 40 for extracting an object 42 from material 10. Extracting element 40 includes a trimmer 44 and a slide 46.

Each of these elements and their functionality will now be discussed in further detail. Material 10 is any suitable material for thermal forming an object; that is, material 10 is any material that becomes malleable in response to a heat treatment. Material 10 may be, for example, elastomeric polymeric material, such as Tru-Train (e.g., 0.03 inch) thermal forming dental material (Tru-Train Plastics, Rochester, Minn.). Material 10 may be provided in a continuous sheet that is sourced from a spool, roll, or the like (not shown), or may be provided in pre-cut portions, where the pre-cut portions are size to fit, for example, object forming element 30. Material 10 may have any suitable shape (e.g., rectangular, square, circular, oval) and thickness (e.g., 0.01 inch, 0.03 inch, 0.05 inch, in the range of 0.01 inch to 0.05 inch; 0.1 inch, 0.12 inch, 0.14 inch, in the range of 0.1 inch to 0.14 inch, or less than 0.1 inch, in the range of 0.05 inch to 0.1 inch, or greater than 0.14 inch). Material 10 can have a substantially uniform thickness across a portion of material 10 and/or a varying thickness across a portion of material 10.

Movable element 12 is any suitable system or device operable to insert material 10 into a heating area 18. Movable element 12 may also be operable to insert material 10 into other portions of system 100, such as object forming element 30 and extracting element 40. In one embodiment, moveable element 12 may include one or more rotatable spools or rolls. Material 10 may contact the rotatable spools, and be caused to move in response to rotation of the rotatable spools. One spool may be arranged for receiving material 10 prior to material 10 entering heating area 18, and another spool may be arranged for receiving material 10 after heating and cutting. Material 10 may be tensed between the spools in operation such that, at least in operation, material 10 is substantially planar between the spools. By the arrangement and rotation of the spools, material 10 may be fed into and through each of heating element 20, object forming element 30, and extracting element 40.

In another embodiment, movable element 12 may include indexing chains (not shown) that use pins, spikes, or other engaging features that pierce and transport material 10. The indexing chains may extend between the various elements of system 100. Similar to the embodiment discussed above, the indexing chains may be operable to feed material 10 into and through each of heating element 20, object forming element 30, and extracting element 40. In yet another embodiment, movable element 12 may include separate portions for inserting material 10 into one or more of heating element 20, object forming element 30, and extracting element 40. For example, material 10 may be precut, and a portion of movable element 12 may operate to dispose the precut portion of material 10 into heating area 18. The same or a different portion of movable element 12 may then operate to transfer the heated precut portion of material 10 from heating area 18 to object forming element 30, where a deformed portion 39 of material 10 is then formed. The same or a different portion of movable element 12 may then operate to transfer deformed portion 39 from object forming element 30 to extracting element 40, where the deformed portion 39 may subsequently be extracted from the material 10.

Supporting member 14 is any suitable apparatus for physically supporting and/or positioning various elements of system 100. For example, supporting member 14 may be a solid object for directly or indirectly supporting and positioning at least one of temperature sensor 24, bottom chamber 36, mold carrier 38, and slide 46. Supporting member 14 may also include portions (not shown) for directly or indirectly supporting and positioning other elements of system 100, such as heating unit 22, top chamber 34, and trimmer 44.

Heating element 20 is any suitable system or device for generating a heating area 18 in which portions of material 10 may be heated. In one embodiment, material 10 is passed through heating element 20 by, e.g., rotation of movable element 12. Material 10 may be continuously passed through heating element 20 or, in some embodiments, a portion of material 10 may be moved to a location proximate to heating element 20, stopped for an amount of time, and then moved to a location proximate other elements of system 100, such as object forming element 30.

Heating element 20 includes a heating unit 22 and a temperature sensor 24. Heating unit 22 is any suitable system or device for directing heat to heating area 18. Heating unit 22 may include one or more heat sources 22 i, or heat sources 22 i may be provided external to heating unit 22. Heat sources 22 i may be any suitable heat source. For example, heat sources 22 i may generate heat by conducting electricity through a resistor, burning gas or other flammable material, generating electromagnetic radiation, etc. Heating unit 22 may be stationary or movable, such that heat may be directed to one or more portions of heating area 18 using a single heat source 22 i. Heating element 20 including heating unit 22 is further discussed with reference to FIGS. 2A to 6.

Temperature sensor 24 is any suitable system or device for measuring a temperature of one or more portions of material 10 located in heating area 18, and may comprise one or more temperature sensing elements 24 i. In one embodiment, temperature sensing elements 24 i are non-contact sensors, in that a temperature of material 10 may be determined without the sensor contacting material 10. For example, temperature sensing elements 24 i may be radiation thermometers (such as a pyrometer, infrared thermal imaging camera, line-measuring thermometer, infrared radiation thermometer, etc.), thermal imagers, radio thermometers, optical pyrometers, fiber optic temperature sensors, etc. In another embodiment, temperature sensing elements 24 i are contact sensors, in that a temperature of material 10 is determined by contacting material 10. For example, temperature sensing elements 24 i may be thermocouples, thermistors, liquid-in-glass thermometers, resistance temperature detectors, filled system thermometers, bimetallic thermometers, semiconductor temperature sensors, etc. Temperature sensing elements 24 i may include any combination of the above. Heating element 20 including temperature sensing elements 24 i is further discussed with reference to FIGS. 2A to 6.

Object forming element 30 is any suitable system or device for disposing heated material 10 over or into at least a portion of a mold 32. Object forming element 30 may receive a portion of material 10 after the portion has been heated by heating element 20. Object forming element 30 may be operatively coupled to mold 32, and operate to dispose the heated portion of material 10 over or into at least a portion of mold 32. Since the heated portion of material 10 is malleable due to the heat treatment, the heated portion of material 10 forms around the contours of mold 32. As a result, deformed portions 39 of material 10 are formed, where deformed portions 39 are shaped to receive mold 32.

In one embodiment, object forming element 30 forms a vacuum so that portions of material 10 are sucked to the inner and/or outer surfaces of mold 32. In this embodiment, object forming element 30 may include top chamber 34 and bottom chamber 36. One or more molds such as mold 32 may be supported by one or more of top chamber 34 and bottom chamber 36. Here, mold 32 is supported by bottom chamber 36. A heated portion of material 10 may be moved to a location between top chamber 34 and bottom chamber 36. Once positioned, movement of material 10 may be stopped. At that point, top chamber 34 and bottom chamber 36 may close towards one another and, together with the heated portion of material 10 located between them, form a sealed chamber. A vacuum may then be formed in the sealed chamber that removes air trapped in the sealed chamber thereby causing the portion of material 10 disposed in the chamber to be pulled over or into mold 32. In another embodiment, object forming element 30 may not form a vacuum. Rather, a portion of material 10 may be pressed over mold 32.

Mold 32 is any suitable mold for forming an object. Mold 32 may be a positive or male mold (where material 10 is formed over mold 32) or may be a negative or female mold (where material 10 is formed inside mold 32). Mold 32 may be made of any suitable solid material, such as metal, silicon, glass, etc. Mold 32 may have any suitable shape. In one embodiment, mold 32 has the shape of a person's teeth (i.e., a physical tooth model). In other embodiments, mold 32 assumes other shapes, such as shapes corresponding to disposable cups, containers, lids, trays, blisters, clamshells, other products for the food, medical, and general retail industries, vehicle door and dash panels, refrigerator liners, utility vehicle beds, plastic pallets, etc.

Extracting element 40 is any suitable system or device for extracting an object 42 from material 10. Extracting element 40 may receive deformed portions 39 of material 10 from object forming element 30, where each deformed portion 39 has a desired shape of object 42. Upon receiving a deformed portion 39, extracting element 40 may remove deformed portion 39 from material 10, thereby providing object 42. Object 42 may be in the shape of a desired object. In some embodiments, object 42 may include residue material that may be further trimmed so as to result in the shape of the desired object.

In one embodiment, extracting element 40 includes a trimmer 44. Trimmer 44 includes cutting edges. Deformed portion 39 may be disposed proximate to the cutting edges of trimmer 44. Trimmer 44 may engage material 10, such that the cutting edges of trimmer 44 physically separate deformed portion 39 from material 10. The separated deformed portions 39 constitute objects 42. In another embodiment, extracting element 40 also includes a slide 46. Slide 46 may be any suitable system or device for receiving and, in some embodiments, transporting objects 42. In one embodiment, slide 46 is an angled member that receives object 42 and causes object 42 to move to a desired location by force of gravity. In other embodiments, different methods of cutting or trimming can be used, including, e.g., automated or manual trimming (or a combination thereof), applying one or more cutting edges, laser trimming or scoring, and the like.

Object 42 may be any object having a desired shape. In one embodiment, object 42 is a patient-removable orthodontic appliance designed to restrain and/or reposition a patient's teeth from a first tooth arrangement (e.g., an initial tooth arrangement) to a second tooth arrangement (e.g., a planned, target, intermediate, or final tooth arrangement). The appliance may be worn by a patient in order to restrain and/or reposition the patient's teeth. The appliance may comprise a shell (e.g., a polymeric shell) or a shell portion defining a plurality of tooth-receiving cavities that are shaped to receive and apply a resilient positioning force for restraining and/or repositioning the teeth. An appliance can fit over all teeth present in an upper or lower jaw, or less then all of the teeth. In some cases, only certain teeth received by an appliance will be repositioned by the appliance while other teeth can provide a base or anchor region for holding the appliance in place as it applies force against the tooth or teeth targeted for repositioning. In some cases, many or most, and even all, of the teeth will be repositioned at some point during an orthodontic treatment. Exemplary appliances, including those utilized in the Invisalign® System, are described in numerous patents and patent applications assigned to Align Technology, Inc. including, for example in U.S. Pat. Nos. 6,450,807, and 5,975,893, and U.S. patent application Ser. No. 12/633,715 (Attorney Docket No. 83289-75154) all which are incorporated by reference herein in their entirety, as well as on the company's website, which is accessible on the World Wide Web (see, e.g., the URL “align.com”). In other embodiments, object 42 may be other types of orthodontic appliances, such as a retainer or tracking template.

System 100 in one embodiment is a thermal forming system including elements for heating material, forming objects in the material, and removing the objects from the material. However, it will be appreciated by those of ordinary skill in the art that such a system could operate equally well in a system having fewer or a greater number of components than are illustrated in FIG. 1. Thus, the depiction of system 100 in FIG. 1 should be taken as being illustrative in nature, and not limiting to the scope of the disclosure.

FIGS. 2A-4B show a simplified heating element 20 according to various embodiments. FIG. 2A is a perspective view of a simplified heating element 20 according to a first embodiment. Heating element 20 includes a plurality of heat sources 22 a, 22 b, 22 c, that are operable to generate and direct heat toward material 10 such that a first portion 10 a, second portion 10 b, and third portion 10 c are respectively heated, where first portion 10 a, second portion 10 b, and third portion 10 c are different from one another.

Heat sources 22 a, 22 b, 22 c may be any suitable system or device for providing heat as previously discussed. In this embodiment, heat sources 22 a, 22 b, 22 c are carbon heaters. Heat sources 22 a, 22 b, 22 c have elongated shapes such that they extend entirely across a width W of material 10. Heat sources 22 a, 22 b, 22 c are arranged parallel to each other in a line corresponding to a direction of a length L of material 10. Heat sources 22 a, 22 b, 22 c are sized so that the heated portions of material 10 a, 10 b, and 10 c constitute at least the entire amount of material 10 used to form object 42 (FIG. 1). Each of heat sources 22 a, 22 b, 22 c is independently controllable so that an amount of heat directed toward material 10 from each heat source is controllable and, as a result, the heat of each of the first portion 10 a, second portion 10 b, and third portion 10 c is controllable.

In one embodiment, an output of one or more of heat sources 22 a, 22 b, 22 c may be controlled. For example, a voltage applied to one or more heat sources 22 a, 22 b, 22 c may be increased or decreased to cause a corresponding increase or decrease in heat generated by one or more of heat sources 22 a, 22 b, 22 c. In another embodiment, a direction of heat communicated by one or more of heat sources 22 a, 22 b, 22 c may be controlled. For example, an orientation of the heat source itself may be adjusted so as to redirect the heat generated by the heat source. For another example, heat directing panels associated with the heat source may be adjusted so as to redirect the heat generated by the heat source. In yet another embodiment, both an output and heat direction of one or more heat sources 22 a, 22 b, 22 c may be controlled.

Temperature sensor 24 in this embodiment includes multiple temperature sensing elements 24 a, 24 b, 24 c. Temperature sensing elements 24 a, 24 b, 24 c may be any suitable system or device for sensing a temperature of material 10 as previously discussed. In this embodiment, temperature sensing elements 24 a, 24 b, 24 c are infrared temperature sensors. Temperature sensing elements 24 a, 24 b, 24 c are operable to sense a temperature of third portion 10 d of material 10, fourth portion 10 e of material 10, and fifth portion 10 f of material 10, respectively. In some embodiments, the temperature sensed portions (10 d, 10 e, 10 f) of material are the same size or larger than the heated portions (10 a, 10 b, 10 c) of material 10. In this embodiment, the temperature sensed portions (10 d, 10 e, 10 f) of material are smaller than the heated portions (10 a, 10 b, 10 c) of material 10.

Temperature sensing elements 24 a, 24 b, 24 c may be provided at any suitable location for measuring a temperature of heated material 10 that is to be used for forming object 42. For example, they may be provided at edges of material 10, in the middle of a width W of material 10, or at other locations along width W. Where multiple temperature sensors are provided, they may be disposed along the length L of material 10 at any suitable distance. In this embodiment, each temperature sensing element (24 a, 24 b, 24 c) corresponds to a heat source (22 a, 22 b, 22 c) and is located opposite a position of the corresponding heat source (22 a, 22 b, 22 c).

Any suitable number of temperature sensing elements 24 a, 24 b, 24 c may be provided for measuring a temperature of heated material 10 that is to be used for forming object 42. For example, a single temperature sensor could be provided, or multiple temperature sensors could be provided. In this embodiment, three temperature sensors are provided, where each temperature sensing element (24 a, 24 b, 24 c) corresponds to a single heat source (22 a, 22 b, 22 c).

In one embodiment, areas of material 10 for which a temperature is measured by a temperature sensor does not change. For example, the temperature sensor may be stationary. In another example, areas of material 10 for which a temperature is measured by a temperature sensor are variable. For example, the temperature sensor may be coupled to and controllable by a motor, actuator, or the like so as to control an orientation of the temperature sensing element.

In this embodiment, heating element 20 also includes a housing 26. Housing 26 operates to at least partially house heat sources 22 a, 22 b, 22 c and, in some cases, reflect heat generated by heat sources 22 a, 22 b, 22 c toward material 10. Housing 26 may insulate or conduct heat, and may be made of any suitable material for doing so such as metals, polymers, minerals, concrete, etc.

Further in this embodiment, heat sources 22 a, 22 b, 22 c are all of the same size, shape, and type. However, in other embodiments, one or more of heat sources 22 a, 22 b, 22 c may have a different size, shape, and/or type. For example, heat sources 22 a, 22 c may be smaller than heat element 22 b. Accordingly, heat sources 22 a, 22 b, 22 c may heat different amounts of material 10, in heat patterns having different shapes, and/or using different heating technology. Similarly, in this embodiment, temperature sensing elements 24 a, 24 b, 24 c are all of the same size, shape, and type. However, in other embodiments, one or more of temperature sensing elements 24 a, 24 b, 24 c may have a different size, shape, and/or type. For example, temperature sensor 24 b may sense a temperature of a larger portion of material 10 than temperature sensing elements 24 a, 24 c. Accordingly, temperature sensing elements 24 a, 24 b, 24 c may sense temperature for different amounts of material 10, in temperature-sensing patterns having different shapes, and/or using different temperature sensing technology.

In operation, material 10 (or a portion of material 10) is inserted into heating area 18 (FIG. 1). Heating area 18 in this embodiment corresponds to areas of material 10 that are heated in response to activating heat sources 22 a, 22 b, 22 c. In this embodiment, material 10 is fed into heating area 18 such that a portion of material 10 will be heated in response to activating heat sources 22 a, 22 b, 22 c. After material 10 is positioned into heating area 18, the positioned material is held stationary. This stationary position may coincide with extracting element 40 controlling trimmer 44 to extract a previously formed object 42 from material 10 (FIG. 1) . At that time, one or more of heat sources 22 a, 22 b, 22 c are activated so as to heat portions 10 a, 10 b, 10 c of material 10. During heating, temperature sensing elements 24 a, 24 b, 24 c operate to measure a temperature of different portions 10 d, 10 e, 10 f of material 10. These temperature measurements are then fed back to a controller (not shown) that operates to control an output of heat sources 22 a, 22 b, 22 c. Heat sources 22 a, 22 b, 22 c may thus be selectively controlled so that the temperatures at different areas of material 10 selectively reach a desired temperature. In one embodiment, the temperatures of portions 10 a, 10 b, 10 c may be controlled to simultaneously reach a desired temperature. In another embodiment, the temperatures of portions 10 a, 10 b, 10 c may be controlled to reach a desired temperature at different times. Once the heated portion(s) of material 10 has been heated to a desired temperature(s), the heated portion(s) may be transported to object forming element 30 (FIG. 1) so as to deform the heated portion(s).

FIG. 2B is a side view of the simplified heating element 20 shown in FIG. 2A. From the side view it is apparent that an object portion 10 z of material is provided, where object portion 10 z is to be used for subsequently forming object 42 (FIG. 1). Object portion 10 z may be any suitable size and any suitable shape for subsequently forming object 42. For example, object portion 10 z may be square, rectangular, circular, oval, etc. Here, object portion 10 z is smaller than portions of material 10 that are heated by heat sources 22 a, 22 b, 22 c. However, in some embodiments, object portion 10 z may be the same size or larger than portions of material 10 that are heated by heat sources 22 a, 22 b, 22 c. Further, according to this embodiment, object portion 10 z is larger than portions of material 10 that are temperature sensed by temperature sensing elements 24 a, 24 b, 24 c. However, in some embodiments, object portion 10 z may be the same size or smaller than portions of material 10 that are temperature sensed by temperature sensing elements 24 a, 24 b, 24 c.

FIG. 3A is a perspective view of a simplified heating element 20 according to a second embodiment. The features discussed with reference to FIGS. 2A and 2B are equally applicable in this embodiment, with the following exceptions. In this embodiment, heat sources 22 a, 22 b, 22 c do not extend entirely across a width W of material 10. Rather, heat sources 22 a, 22 b, 22 c extend only partially across the width W. Further, heat sources 22 a, 22 b, 22 c are staggered across length L. That is, heat sources 22 a, 22 c are disposed over a first half of width W, and heat element 22 b is disposed over a second half of width W different than the first half. By one or more of their size and positioning, heat sources 22 a, 22 b, 22 c are disposed so that object portion 10 z (FIG. 3B), which is used for subsequently forming object 42, may include both heated portions and non-heated portions.

In this embodiment, temperature sensing elements 24 a, 24 b, 24 c are also staggered. Temperature sensing elements 24 a, 24 b, 24 c are located such that temperature sensed portions 10 d, 10 e, 10 f of material 10 correspond to heated portions 10 a, 10 b, 10 c. Here, temperature sensed portions 10 d, 10 e, 10 f only sense heated portions of material 10. However, in some embodiments, one or more temperature sensed portions 10 d, 10 e, 10 f may include non-heated portions of material 10. In some embodiments, one or more of temperature sensed portions 10 d, 10 e, 10 f may include only non-heated portions of material 10.

FIG. 3B is a side view of the simplified heating element 20 shown in FIG. 3A. From the side view it is apparent that, even when heat sources 22 a, 22 b, 22 c operate to generate heated portions of material 10 with non-heated portions remaining, object portion 10 z may extend across a length L of material including both heated and non-heated portions of material 10.

FIG. 4A is a perspective view of a simplified heating element 20 according to a third embodiment. The features discussed with reference to FIGS. 2A to 3B are equally applicable in this embodiment, with the following exceptions. In this embodiment, the heat sources (not shown) are external and generate heat that is directed by housing 26.

Housing 26 in this embodiment includes heat directing chambers 26 a, 26 b. Heat directing chambers 26 a, 26 b are defined by walls of housing 26. Heat is provided from one or more external heat sources and, at least as illustrated in FIG. 4A, enters apertures provided at a top of heat directing chambers 26 a, 26 b. Heat directing chambers 26 a, 26 b then operate to direct the heat toward material 10 so as to heat portions 10 a, 10 b of material 10. The heat directed by heat directing chambers 26 a, 26 b may be generated by any suitable source, as previously discussed.

In one embodiment, an orientation of one or more of heat directing chambers 26 a, 26 b is fixed. For example, heat directing chambers 26 a, 26 b may be formed as a single unit with housing 26. In another embodiment, an orientation of one or more of heat directing chambers 26 a, 26 b is variable. For example, heat directing chambers 26 a, 26 b may not form a single unit with housing 26, but rather may be coupled to and controllable by motors, actuators, and the like.

In this embodiment, two heat chambers are provided. However, in other embodiments, one or more heat chambers may be provided. In this embodiment, heat chambers 26 a, 26 b are cylindrical in shape. However, heat chambers 26 a, 26 b may have any suitable shape, including shapes having cross-sections that are square, rectangular, trapezoidal, circular, oval, etc. Heat chambers 26 a, 26 b are all of the same size and shape in this embodiment. However, in other embodiments, heat chambers 26 a, 26 b may have a different size or shape. For example, heat chamber 26 a may be larger than heat chamber 26 b.

Further in this embodiment, only a single temperature sensing element 24 a is provided. Accordingly, temperature sensing element 24 a is operable to measure a temperature of a single portion 10 d of material 10. Temperature sensed portion 10 d in this embodiment fully encompasses the heated portions 10 a, 10 b of material 10. However, in other embodiments, temperature sensed portion 10 d may only encompass a portion of one or more of heated portions 10 a, 10 b, or none of heated portions 10 a, 10 b.

FIG. 4B is a side view of the simplified heating element 20 shown in FIG. 4A. From the side view it is apparent that a single temperature sensing element 24 a is operable to sense the temperature of a portion of material 10 including object portion 10 z. It is further apparent that the portions of material 10 heated by heat directed through heat directing chambers 26 a, 26 b may not overlap along the length L of material 10. However, in other embodiments, such portions may partially or fully overlap with one another.

FIGS. 2A to 4B show various embodiments of a simplified heating element 20. However, it will be appreciated by those of ordinary skill in the art that heating element 20 could operate equally well having fewer or a greater number of components than are illustrated in

FIGS. 2A to 4B. Thus, the depiction of heating element 20 in FIGS. 2A to 4B should be taken as being illustrative in nature, and not limiting to the scope of the disclosure.

FIGS. 5A-5C show heated portions of material 10 according to various embodiments. FIG. 5A shows heated portions 10 a, 10 b, 10 c of material 10 according to a first embodiment. In this embodiment, heated portions 10 a, 10 b, 10 c may correspond to those generated by heat sources 22 a, 22 b, 22 c discussed with reference to FIGS. 2A and 2B. Material 10 includes object portion 10 z, where object portion 10 z is to be used for subsequently forming object 42 (FIG. 1). Further, object portion 10 z includes a deforming portion 10 k, where deforming portion 10 k will be formed in or around mold 32 by object forming element 30 (FIG. 1).

In this embodiment, deforming portion 10 k is in the shape of patient-removable orthodontic appliance to be disposed over a patient's teeth. However, deforming portion 10 k may be any suitable shape for forming a desired object, where the object may be any suitable object as previously discussed.

Heated portions 10 a, 10 b, 10 c in this embodiment collectively encompass the entire object portion 10 z, as well as the entire deforming portion 10 k. Each heated portion 10 a, 10 b, 10 c also includes a unique portion of deforming portion 10 k. Accordingly, a heat of different portions of deforming portion 10 k may be selectively controlled. In this fashion, some portions of material 10 which require greater malleability for molding can be selectively heated, whereas other portions that do not require such level of malleability can also be selectively heated. For example, the portions of deforming portion 10 k that require greater malleability can be selectively heated to a greater degree, while other portions of deforming portion 10 k that do not require a great degree of malleability can be selectively heated to a degree lower than that of the aforementioned portions. Similarly, portions of object portion 10 z that require greater malleability for molding can be selectively heated to a greater degree, while other portions of object portion 10 z that do not require a great degree of malleability can be selectively heated to a degree lower than that of the aforementioned portions.

In some embodiments, different portions of material 10 may be selectively heated to ensure a consistent heating across some or all of material 10. For example, by feedback from temperature sensor 24, heating element 20 may be controlled so that deforming portion 10 k and/or object portion 10 z have the same temperature (FIG. 1). Further, the different portions of material 10 may be heated at different rates or at the same rate, so as to achieve the same or different temperatures. In some cases, a desired temperature of one or more portions of material 10 may be achieved without overshooting. That is, by use of temperature sensor 24, heating element 20 may be controlled so that a desired temperature of one or more portions of material 10 is reached without a temperature of one of more portions of material 10 exceeding the desired temperature (FIG. 1).

FIG. 5B shows heated portions 10 a, 10 b, 10 c of material 10 according to a second embodiment. In this embodiment, heated portions 10 a, 10 b, 10 c may correspond to those generated by heat sources 22 a, 22 b, 22 c discussed with reference to FIGS. 3A and 3B. The features discussed with reference to FIG. 5A are equally applicable in this embodiment, with the following exceptions.

In this embodiment, heated portions 10 a, 10 b, 10 c do not encompass the entire object portion 10 z, nor do they encompass the entire deforming portion 10 k. Rather, heated portions 10 a, 10 b encompass a portion of deforming portion 10 k, and heated portion 10 b does not encompass any portion of deforming portion 10 k, but does encompass a portion of object portion 10 z. Further, heated portions 10 a, 10 b, 10 c do not overlap with one another. In this fashion, some portions of object portion 10 z may be heated independently of heating deforming portion 10 k.

FIG. 5C shows heated portions 10 a, 10 b of material 10 according to a third embodiment. In this embodiment, heated portions 10 a, 10 b may correspond to those generated by heat communicated via heat directing chambers 26 a, 26 b discussed with reference to FIGS. 4A and 4B. The features discussed with reference to FIGS. 5A and 5B are equally applicable in this embodiment, with the following exceptions.

In this embodiment, heated portions 10 a, 10 b do not encompass the entire deforming portion 10 k, nor do they encompass the entire object portion 10 z. Rather, heated portions 10 a, 10 b encompass only a portion of each of deforming portion 10 k and object portion 10 z. In this fashion, portions of deforming portion 10 k and object portion 10 z may be directly heated whereas other portions may not be directly heated.

FIGS. 5A to 5C show various embodiments for heating portions of material 10. However, it will be appreciated by those of ordinary skill in the art that more or fewer portions of material 10 may be heated than are illustrated in FIGS. 5A to 5C. Thus, the depiction of heated portions of material 10 in FIGS. 5A to 5C should be taken as being illustrative in nature, and not limiting to the scope of the disclosure.

FIG. 6 shows a heating element 20 according to an embodiment. In this embodiment, heating element 20 includes a heat source 22 a, a temperature sensing element 24 a, a machine controller 27, a heat source controller 28, and a signal conditioner 29. For each of the elements identified with the same number as previously used herein, the same discussion as that previously articulated is applicable. The newly illustrated elements and their relationship to those already presented will now be discussed.

Machine controller 27 is any suitable electronic computing device operable to receive temperature signals from temperature sensing element 24 a and communicate thermal control signals to heat source controller 28. Machine controller 27 is electrically connected to temperature sensing element 24 a via signal conditioner 29, where cables may be provided to electrically couple machine controller 27 to signal conditioner 29 and signal conditioner 29 to temperature sensing element 24 a. Machine controller 27 is electrically connected to heat source 22 a via heat source controller 28, where cables may be provided to electrically couple machine controller 27 to heat source controller 28 and heat source controller 28 to heat source 22 a.

Signal conditioner 29 is any suitable electronic computing device operable to perform signal conditioning on a received signal. For example, signal conditioner 29 may filter noise from a received signal, amplify certain bandwidths of a received signal, etc. Signal conditioner 29 receives temperature signals from sensing element 24 a, where the temperature signals indicate a temperature of material within temperature sensed portion 10 d. After receiving the temperature signals, signal conditioner 29 performs signal processing on the received signals, and then communicates the processed temperature signals to machine controller 27.

In some embodiments, there is no signal conditioner 29. Rather, machine controller 27 directly receives temperature signals from temperature sensing element 24 a. In other embodiments, the functionality of signal conditioner 29 is performed by machine controller 27.

After receiving the temperature signals, machine controller 27 may control an output of heat source 22 a based on the received temperature signals and a desired temperature. Heat source 22 a may be controlled to heat portions of material 10 in any of the fashions previously discussed. The desired temperature may be received or determined in a variety of ways, as further discussed with reference to FIGS. 7 and 8. In controlling the output of heat source 22 a, machine controller 27 may communicate a thermal control signal to heat source controller 28, where the thermal control signal instructs heat source controller 28 to increase or decrease an output of heat source 22 a. In some embodiments, the thermal control signal may also or alternatively instruct heat source controller 28 to change a direction of the output of heat source 22 a.

Heat source controller 28 is any suitable electronic computing device operable to control an output of heat source 22 a based on a received thermal control signal. In one embodiment, heat source controller 28 controls an output of heat source 22 a by communicating a power signal to heat source 22 a. The characteristics of the power signal vary depending on the type of technology comprising heat source 22 a. In some embodiments, the power signal may be a low voltage digital signal. In other embodiments, the power signal may be a high voltage analog signal. In this embodiment, heat source 22 a is a carbon emitter, and the power signal ranges from 0 to 70 VAC. Further, in this embodiment, heat source controller 28 increases a voltage of the power signal in response to thermal control signal indicating an increase in output from heat source 22 a, and heat source controller 28 decreases a voltage of the power signal in response to thermal control signal indicating a decrease in output from heat source 22 a.

In another embodiment, heat source controller 28 controls a direction of heat source 22 a by communicating an adjustment signal to heat source 22 a. The characteristics of the adjustment signal vary depending on the structure of heat source 22 a. In some embodiments, the adjustment signal may be an analog or digital signal instructing heat source 22 a to change its orientation. In other embodiments, the adjustment signal may be an analog or digital signal instructing a heat directing chamber 26 a, 26 b to change its orientation.

In some embodiments, there is no heat source controller 28. Rather, machine controller 27 directly communicates thermal control signals to heat source 22 a. In other embodiments, the functionality of heat source controller 28 is performed by machine controller 27. Further, although FIG. 6 shows only a single heat source 22 a and temperature sensing element 24 a, numerous other possibilities and variations as previously discussed are also within the scope of this application.

In one embodiment, machine controller 27 is electronically coupled to other elements of system 100 discussed with reference to FIG. 1. For example, machine controller 27 may be electronically coupled to moveable element 12, object forming element 30, and/or extracting element 40. Machine controller 27 may then be operable to receive information from each of these elements, and communicate control signals to each of these elements for controlling an operation thereof. Further processing by machine controller 27 is discussed with reference to FIGS. 7 and 8.

Heating element 20 in one embodiment includes machine controller 27, heat source controller 28, and signal conditioner 29. However, it will be appreciated by those of ordinary skill in the art that heating element 20 could operate equally well in a heating element 20 having fewer or a greater number of components than are illustrated in FIG. 6. Thus, the depiction of heating element 20 in FIG. 6 should be taken as being illustrative in nature, and not limiting to the scope of the disclosure.

FIG. 7 is a flowchart 700 depicting example operations for thermal forming an object in accordance with a first embodiment. In operation 702, a mold is provided. For example, mold 32 may be disposed in mold carrier 38 of object forming element 30 (FIG. 1). Mold 32 may thus be operatively coupled to object forming element 30. In some embodiments mold 32 may be positioned into mold carrier 38 by a mold positioning device (not shown). For example, the mold positioning device may be a robotic arm for moving objects between locations. Accordingly, the mold positioning device may operate to provide and remove mold 32 to and from mold carrier 38.

In operation 704, a material 10 is inserted into a heating area 18 (FIG. 1). Material 10 may be inserted into heating area 18 using any suitable means. For example, material 10 may be inserted into heating area 18 via movable element 12 (FIG. 1). In some embodiments, a portion of material 10 is inserted into heating area 18 and subsequently held stationary in heating area 18 during a subsequent heat treatment. In other embodiments, material 10 may be continuously transported through heating area 18 without stoppage. In one embodiment, machine controller 27 (FIG. 6) operates to control movable element 12.

In operation 706, material 10 is heated using a plurality of independently controllable heat sources 22 i (FIG. 1) that heat different areas of the material. Various portions of material 10 may be heated using any of the independently controllable heat sources 22 i and/or heat directing chambers 26 a, 26 b as previously discussed. In one embodiment, machine controller 27 operates to control independently controllable heat sources 22 i and/or heat directing chambers 26 a, 26 b so as to heat a portion of material 10 located in heating area 18.

In operation 708, the heated material 10 is disposed over or into at least a portion of the mold 32. The heated material 10 may be disposed over or into mold 32 using any suitable process as previously discussed. In one embodiment, machine controller 27 operates movable element 12 to move the heated material 10 from heating area 18 to a location between top chamber 34 and bottom chamber 36 (FIG. 1). Machine controller 27 may then control object forming element 30 to cause top chamber 34 and bottom chamber 36 to form a sealed chamber with the heated material 10 located therein. Machine controller 27 may then control object forming element 30 to create a vacuum within the sealed chamber, thereby causing portions of the heated material 10 to be formed over contours and/or inside cavities of mold 32.

It should be appreciated that the specific operations illustrated in FIG. 7 provide a particular method of thermal forming an object, according to an embodiment of the present invention. Other sequences of operations may also be performed according to alternative embodiments. For example, alternative embodiments of the present invention may perform the operations outlined above in a different order. Moreover, the individual operations illustrated in FIG. 7 may include multiple sub-operations that may be performed in various sequences as appropriate to the individual operation. Furthermore, additional operations may be added or removed depending on the particular applications. One of ordinary skill in the art would recognize and appreciate many variations, modifications, and alternatives. For example, one or more movable element 12 and object forming element 30 may include their own electronic computing device for controlling that element. Accordingly, machine controller 27 need not control the operation of each of these elements.

FIG. 8 is a flowchart 800 depicting example operations for thermal forming an object in accordance in accordance with a second embodiment. In operation 802, a mold 32 (FIG. 1) is provided, similar to operation 702. In operation 804, a mold identifier for identifying the mold 32 is received. In one embodiment, machine controller 27 (FIG. 6) receives the mold identifier. The mold identifier may be received from any suitable source. For example, it may be input by a user. For another example, the mold identifier may be located on or in mold 32, and the mold identifier may be read from mold 32 using any suitable technology. For example, the mold identifier may be provided in an RFID chip which may be read by machine controller 27. For another example, the mold identifier may be read using a bar code scanner electronically coupled to or included in machine controller 27.

In one embodiment, machine controller 27 also or alternatively receives a material identifier for identifying material 10. The material identifier may be received from any suitable source. For example, it may be input by a user. For another example, the material identifier may be located on or in material 10, and the material identifier may be read from material 10 using any suitable technology. For example, the material identifier may be provided in an RFID chip which may be read by machine controller 27. For another example, the material identifier may be read using a bar code scanner electronically coupled to machine controller 27.

In operation 806, mold process information is determined based on the mold identifier. In some embodiments, the mold process information may also or alternatively be determined based on the material identifier. Mold process information may include any suitable information for forming object 42 (FIG. 1). For example, mold process information may include control information for controlling one or more of the elements of system 100. In one embodiment, mold process information includes heating information, such as a desired heating temperature at various locations of material 10, a desired heating time at various locations of material 10, a maximum cooling period between heating material 10 and disposing the heated material over or into mold 32, a maximum heating temperature for any portion of material 10, etc. Machine controller 27 may use this information to subsequently control the various elements, such as movable element 12, heating element 20, etc. of system 100 (FIG. 1). In one embodiment, mold process information for various different molds 32 is pre-stored in machine controller 27 and associated with mold identifiers and/or material identifiers, so that machine controller 27 may subsequently determine or read such information in response to receiving the mold identifier and/or material identifier.

In operation 808, a material 10 is inserted into a heating area 18 (FIG. 1), similar to operation 704. In operation 809, a portion of material 10 is heat treated by heating element 30 (FIG. 1). The heat treatment of operation 809 includes one or more operations. In one embodiment, operation 809 includes operations 810, 812, and 814.

In operation 810, the material 10 is heated using a plurality of independently controllable heat sources 22 i (FIG. 1) that heat different areas of the material 10, similar to operation 706. In operation 812, a temperature of the material 10 is monitored during heating. Machine controller 27 may monitor the temperature of the material 10 using temperature sensor 24 (FIG. 1). Temperatures of portions of the material 10 may be monitored in accordance with any of the previously discussed embodiments.

In operation 814, the heat sources 22 i are controlled based on the monitored temperature. Machine controller 27 may control an output or operation of heat sources 22 i and/or heat directing chambers 26 a, 26 b based on the temperature monitored using temperature sensor 24. In one embodiment, the heat sources 22 i and/or heat directing chambers 26 a, 26 b may be controlled so that the temperatures at different areas of the material 10 selectively reach the desired temperature. A temperature at different areas of material 10 may be selectively controlled in response to independently monitoring a temperature at different areas of material 10.

The desired temperature may be determined in any suitable fashion. For example, a user may input the desired temperature into machine controller 27. For another example, the desired temperature may be included in the mold process information and thus obtained using a mold identifier associated with mold 32 and/or a material identifier associated with material 10. In one embodiment, the desired temperature is reached without overshooting. That is, by use of temperature sensor 24, heating sources 22 i and/or directing chambers 26 a, 26 b may be controlled so that the desired temperature of one or more portions of material 10 is reached without a temperature of one of more portions of material 10 exceeding the desired temperature.

In operation 816, a quality of the heated material 10 is checked by comparing the temperature in each of the different areas to a desired temperature. The quality of the heated material 10 may be determined based on differences between a measured and desired temperature. For example, if the measured temperature exceeds the desired and/or maximum temperature, the quality of the material 10 may be determined to be unacceptable. For another example, if the measured temperature significantly exceeds the desired and/or maximum temperature, the quality of the material 10 may be determined to be unacceptable.

In some embodiments, an amount of time at which the temperature difference exists may also be taken into consideration. For example, if the measured temperature exceeds the desired and/or maximum temperature for less than a set time, the quality of the material 10 may be determined to be acceptable. On the other hand, if the measured temperature exceeds the desired and/or maximum temperature for an amount of time equal to or greater than a set time, the quality of the material 10 may be determined to be unacceptable. In one embodiment, machine controller 27 may make such determinations based on temperature signals received from temperature sensor 24 and mold process information. In some embodiments, operation 816 may be performed as part of operation 809.

In operation 818, the heated material 10 is disposed over or into at least a portion of the mold 32, similar to operation 708. In operation 820, the heated material 10 is displaced from the mold 32. Any suitable technique for displacing the heated material 10 from the mold after thermal forming the heated material 10 may be used. For example, the deformed, heated material 10 may be air-ejected from mold 32, stripped off of mold 32 using a stripper plate, etc.

As a result of displacing the heated material 10 from the mold 32, deformed portions 39 will be formed in the material 10.

In operation 822, the displaced material 10 is trimmed so as to form an object 42. The displaced material 10 (i.e., deformed portions 39) may be trimmed by trimmer 44 (FIG. 1). Any of the previously discussed techniques for trimming may be used. For example, trimmer 44 may engage material 10 such that cutting edges of trimmer 44 physically separate deformed portion 39 from material 10. As a result of trimming, apertures may be formed in material 10.

It should be appreciated that the specific operations illustrated in FIG. 8 provide a particular method of thermal forming an object, according to an embodiment of the present invention. Other sequences of operations may also be performed according to alternative embodiments. For example, alternative embodiments of the present invention may perform the operations outlined above in a different order. Moreover, the individual operations illustrated in FIG. 8 may include multiple sub-operations that may be performed in various sequences as appropriate to the individual operation. Furthermore, additional operations may be added or removed depending on the particular applications. One of ordinary skill in the art would recognize and appreciate many variations, modifications, and alternatives.

FIG. 9 is a diagram of an electronic computing device 900 according to an example embodiment. The various elements in the previously described system diagrams (e.g., machine controller 27, heat element controller 28, and/or signal conditioner 29) may use any suitable number of subsystems in the computing device to facilitate the functions described herein. Examples of such subsystems or components are shown in FIG. 9. The subsystems shown in FIG. 9 are interconnected via a system bus 910. Additional subsystems such as a printer 920, keyboard 930, fixed disk 940 (or other memory comprising tangible, non-transitory computer-readable media), monitor 950, which is coupled to display adapter 955, and others are shown. Peripherals and input/output (I/O) devices (not shown), which couple to I/O controller 960, can be connected to the computer system by any number of means known in the art, such as serial port 965. For example, serial port 965 or external interface 970 can be used to connect the computing device to a wide area network such as the Internet, a mouse input device, or a scanner. The interconnection via system bus allows the central processor 980 to communicate with each subsystem and to control the execution of instructions from system memory 990 or the fixed disk 940, as well as the exchange of information between subsystems. The system memory 990 and/or the fixed disk 940 may embody a tangible, non-transitory computer-readable medium.

The software components or functions described in this application may be implemented as software code to be executed by one or more processors using any suitable computer language such as, for example, Java, C++ or Perl using, for example, conventional or object-oriented techniques. The software code may be stored as a series of instructions, or commands on a tangible, non-transitory computer-readable medium, such as a random access memory (RAM), a read-only memory (ROM), a magnetic medium such as a hard-drive or a floppy disk, or an optical medium such as a CD-ROM. Any such computer-readable medium may also reside on or within a single computational apparatus, and may be present on or within different computational apparatuses within a system or network.

Embodiments of the present invention can be implemented in the form of control logic in software or hardware or a combination of both. The control logic may be stored in an information storage medium as a plurality of instructions adapted to direct an information processing device to perform a set of operations disclosed in embodiments of the present invention. Based on the disclosure and teachings provided herein, a person of ordinary skill in the art will appreciate other ways and/or methods to implement the present invention.

The use of the terms “a” and “an” and “the” and similar referents in the context of describing embodiments (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. The term “connected” is to be construed as partly or wholly contained within, attached to, or joined together, even if there is something intervening. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate embodiments and does not pose a limitation on the scope unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of at least one embodiment.

Preferred embodiments are described herein, including the best mode known to the inventors. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for embodiments to be constructed otherwise than as specifically described herein. Accordingly, suitable embodiments include all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is contemplated as being incorporated into some suitable embodiment unless otherwise indicated herein or otherwise clearly contradicted by context. The scope of the invention should, therefore, be determined not with reference to the above description, but instead should be determined with reference to the pending claims along with their full scope or equivalents. 

1. A method for thermal forming an object, comprising: providing a mold; inserting a material into a heating area; heating the material using a plurality of independently controllable heat sources that heat different areas of the material; and disposing the heated material over or into at least a portion of the mold.
 2. The method of claim 1, further comprising monitoring a temperature of the material during heating.
 3. The method of claim 2, wherein heating the material includes controlling the heat sources based on the monitored temperature so that the temperatures at the different areas of the material selectively reach a desired temperature.
 4. The method of claim 3, wherein the desired temperature is reached without overshooting.
 5. The method of claim 2, wherein monitoring a temperature of the material during heating includes independently monitoring the different areas of the material.
 6. The method of claim 1, further comprising: comparing the temperature in each of the different areas of the material to a desired temperature.
 7. The method of claim 1, further comprising: receiving a mold identifier identifying the mold; and determining heating information based on the mold identifier, wherein the heat sources are controlled based on the determined heating information.
 8. The method of claim 1, further comprising: displacing the heated material from the mold; and trimming the displaced material so as to form an orthodontic appliance.
 9. The method of claim 1, wherein the mold is a physical tooth model.
 10. A system for thermal forming an object, comprising: a movable element operable to insert a material into a heating area; a heating unit operable to heat the material using a plurality of independently controllable heat sources that heat different areas of the material when the material is located in the heating area; a controller electronically coupled to the heating heat sources for controlling an output of the heat sources; and an object forming element, operatively coupled to a mold, positioned to receive the heated material, and configured to dispose the heated material over or into at least a portion of the mold.
 11. The system of claim 10, further comprising a temperature sensor operable to monitor a temperature of the material during heating.
 12. The system of claim 11, wherein the temperature sensor includes an infrared temperature sensor.
 13. The system of claim 10, further comprising a temperature sensing element for each heat source, each temperature sensing element operable to monitor a temperature in an area of the material while that area is heated by a corresponding heat source.
 14. The system of claim 13, wherein the controller is electronically coupled to the temperature sensing elements and controls the output of the heat sources based on the monitored temperature in each area of the material.
 15. The system of claim 10, wherein the heat sources are configured such that, when operated simultaneously, the heat sources heat areas of the material that are subsequently disposed over or into at least a portion of the mold by the object forming element.
 16. A heating element for heating a material used to form an object in a thermal forming process, comprising: a plurality of independently controllable heat sources operable to heat different portions of the material; a temperature sensor for monitoring a temperature of one or more portions of the material; and a control device electrically coupled to the heat sources and the temperature sensor for controlling the heat sources based on the monitored temperature.
 17. The heating element of claim 16, wherein the heat sources are operable to heat at least one portion of the material to be contoured to a surface of the object and at least one portion of the material that is not contoured to a surface of the object.
 18. The heating element of claim 16, wherein the temperature sensor includes a temperature sensing element for each heat source, each heat source directs heat in a direction, and each temperature sensing element is positioned a distance away from a corresponding heat source in the direction which the heat source directs heat towards.
 19. The heating element of claim 16, wherein the control device controls the heat sources so that the temperatures at different portions of the material selectively reach a desired temperature.
 20. The heating element of claim 16, wherein at least one heat source is sized to extend only partially across a width of the material. 